Fitting for dental syringe tip

ABSTRACT

A fitting for releasably and sealingly connecting a conduit to a medical instrument. The fitting comprises a body having a proximal end, a distal end and a longitudinal axis extending between the ends. The body has a recess extending on the axis, a bottom adjacent its proximal end and is open at its distal end. The bottom of the body includes first and second passages for flow of first and second fluids. The fitting further includes a quick-connect device mounted in the recess and having a gripping mechanism. The conduit is receivable in the gripping mechanism for movement of the conduit in proximal and distal directions with respect to the body. The gripping mechanism permits one end of the conduit to be pushed through an opening of the quick-connect device to a position in which a tubular connector provides a sealing connection between a central passageway in the conduit and the first passage in the bottom of the body. The gripping mechanism is operable to apply a progressively increasing gripping force to the conduit as the conduit moves away from the bottom until the conduit reaches a position in which the gripping force prevents substantial further movement of the conduit away from the bottom. The fitting further includes a manually operable device for moving the gripping mechanism in a proximal direction relative to the body to cause the gripping mechanism to move radially outward to release the conduit so it can be removed from the body.

BACKGROUND OF THE INVENTION

This invention relates to air-water syringes, and more specifically tofittings for connecting a syringe tip to a hand-piece of an air-watersyringe.

Air-water syringes are used by dentists and dental technicians for manydental procedures, such as cleaning debris from a patient's teeth andmouth. The teeth and mouth are cleaned by spraying a stream of water,air or a combination of water and air from the syringe. A typicalair-water syringe has a hand-piece and a syringe tip releasably attachedto the hand-piece.

Many dentists use disposable syringe tips to avoid spreading infectiousdiseases from one patient to another. A typical disposable air-watersyringe tip has discrete air and water passageways for communicationwith air and water passageways of the hand-piece.

Disposable tips are typically received in a connector which is adaptedto connect the tip to the hand-piece. The tips are held in place byturning the connector which includes one or more parts which clamp downon the tube. These connectors have a disadvantage in that the tip maynot be securely held in the hand-piece if the connector is notadequately screwed onto the hand-piece. This may result in leakage frombetween the hand-piece and tip or the tip being ejected into thepatient's mouth which could result in injury to the patient.Furthermore, the time required to loosen the connector, replace the tipand reattach and tighten the connector is significant considering thesesteps are repeated several times a day.

Quick-connect type fittings which are presently available eliminate theneed for tightening a connector, these fittings, however, requirespecially formed disposable tips which are expensive to manufacture.These fittings typically include many parts including springs which canwear over time thus increasing the chances of ejecting a tip into apatient's mouth.

Accordingly, there is a need for a quick-connect fitting for connectinga dental syringe tip to a dental syringe hand-piece which is simple touse, reliable and relatively inexpensive to manufacture, and can be usedwith different types of syringe tips.

SUMMARY OF THE INVENTION

Among the several objects of this invention may be noted the provisionof an improved fitting for connecting a syringe tip to a medical syringewhich requires only insertion of the tip into the fitting to lock thetip in place; the provision of such a fitting which securely holds thetip in place without tightening a coupling over the tip; the provisionof such a fitting which allows for rotation of the syringe tip withinthe fitting; the provision of such a fitting which is adaptable for usewith different types of syringes; and the provision of such a fittingwhich is economical and easy to manufacture.

Generally, a fitting of this invention is for releasably and sealinglyconnecting a conduit to a medical instrument. The medical instrument hasa socket for receiving the fitting and first and second ports fortransfer of first and second fluids to and from the socket. The conduithas a central passageway therethrough for conducting the first fluid andone or more peripheral passageways therethrough for conducting saidsecond fluid. The fitting comprises a body having a proximal end, adistal end and a longitudinal axis extending between the ends. The bodyhas a recess extending on the axis from the distal end toward andterminating short of the proximal end thereof and a bottom adjacent itsproximal end. The body is open at its distal end and is formed forattachment to the medical instrument with the proximal end of the bodypositioned in the socket of the instrument. The fitting further includesfirst and second passages through the bottom of the body for flow of thefirst and second fluids respectively. A quick-connect device is mountedin the recess in the body adjacent the distal end of the body forallowing quick connection of the conduit to the body and quickdisconnection of the conduit from the body. The quick-connect device hasan opening therethrough generally coaxial with the longitudinal axis ofthe body and comprises a gripping mechanism adjacent the opening. Theconduit being receivable within the gripping mechanism for axialmovement of the conduit in proximal and distal directions with respectto the body. Movement of the conduit in the proximal direction allowsthe gripping mechanism to move radially outward relative to thelongitudinal axis of the body and movement in the distal directioncauses the gripping mechanism to move radially inward toward thelongitudinal axis. The gripping mechanism permits one end of theconduit, constituting its proximal end, to be pushed through the openingof the quick connect device to an initial position in the body recessadjacent the bottom of the body. The initial position of the conduit isone in which a tubular connector provides a fluid-tight sealingconnection between the central passageway in the conduit and the firstpassage in the bottom of the body. The gripping mechanism is responsiveto a force on the conduit in a distal direction to permit the conduit tomove a limited distance away from the bottom of the body. The grippingmechanism is operable to apply a progressively increasing gripping forceto the conduit as the conduit moves away from the bottom until theconduit reaches an operating position in which the gripping forceprevents substantial further movement of the conduit in a distaldirection away from the bottom. The conduit is in its operating positionwhen the proximal end of the conduit is spaced from the bottom of thebody to provide a cavity therebetween allowing fluid communicationbetween the second passage in the bottom of the body and the one or moreperipheral passageways in the conduit. The tubular connector is adaptedto maintain the fluid-tight sealing connection between the first passagein the bottom of the body and the central passageway in the conduit whenthe conduit is in its operating position. The fitting further includesmanually operable means for moving the gripping mechanism in a proximaldirection relative to the body to allow the gripping mechanism to moveradially outward to release the conduit so it can be removed from thebody.

In another aspect of the invention, a medical syringe comprises ahand-piece for transporting first and second fluids between a patientand the syringe. The medical syringe further includes a syringe tiphaving a central passageway therethrough for conducting the first fluidand one or more peripheral passageways therethrough for conducting thesecond fluid. The improvement in the medical syringe comprises a tipconnector assembly for releasably and sealingly connecting the syringetip to the hand-piece. The tip connector assembly is similar to thefitting described above.

Generally, a method of the present invention is for connecting a syringetip to a hand-piece used to transport first and second fluids between apatient and the hand-piece. The syringe tip is of the type having acentral passageway therethrough for conducting the first fluid and oneor more peripheral passageways therethrough for conducting the secondfluid. The hand-piece includes a fitting as described above. The methodincludes pushing the syringe tip through the opening in the grippingdevice to an initial position in which the proximal end of the syringetip is adjacent the bottom of the body and the central passageway in thesyringe tip has a fluid-tight sealing connection to the first passage inthe bottom of the body. The method further includes moving the syringetip in a direction away from the bottom of the body thereby causing thegripping mechanism to apply a progressively increasing gripping force tothe syringe tip until the syringe tip reaches an operating position inwhich the gripping force prevents substantial further movement of thesyringe tip in a distal direction away from the bottom while maintainingthe fluid-tight sealing connection. The operating position of thesyringe tip is one in which the proximal end of the syringe tip isspaced from the bottom of the body to provide a cavity therebetweenallowing fluid communication between the second passage in the bottom ofthe body and the one or more peripheral passageways in the syringe tip,and in which the fluid-tight sealing connection between the firstpassage in the bottom of the body and the central passageway in thesyringe tip is maintained.

Another method of this invention is for connecting and disconnecting adisposable syringe tip to and from a hand-piece used to transport firstand second fluids between a patient and the hand-piece. The hand-piecehas a fitting as described above. The method comprises pushing theproximal end of the syringe tip in a proximal direction into the recessin the body for engagement by the gripping mechanism; applying a forceupon the manually operable means in a proximal direction to disengagethe syringe tip from the gripping mechanism; and removing the syringetip from the fitting.

In another aspect of this invention, a connector is used with thefitting described above. The connector comprises a base, a centralmember extending from the base, and a tubular member extending from oneend of the central member and having a generally constant diameter sizedfor insertion into the central passageway of the syringe tip. Theconnector is configured such that when the base is positioned betweenthe fitting and the dental syringe the central member extends throughthe first passage in the body and the tubular member extends into thefluid passageway of the syringe tip. The connector has an openingextending through a central longitudinal axis of the connector forproviding fluid communication between the dental syringe and the centralpassageway of the syringe tip. The connector is releasably and removablyattached to the body whereby the connector may be readily replaced.

Other objects and features will be in part apparent and in part pointedout hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a first embodiment of a fitting ofthe present invention connecting a syringe tip to a dental syringe;

FIG. 2 is a cross-sectional view of a second embodiment of a fitting ofthe present invention connecting a syringe tip to a dental syringe;

FIG. 3 is a cross-sectional view of a third embodiment of a fitting ofthe present invention connecting a syringe tip to a dental syringe;

FIG. 4 is a cross-sectional view of a fourth embodiment of a fitting ofthe present invention connecting a syringe tip to a dental syringe;

FIG. 5 is a cross-sectional view of a fifth embodiment of a fitting ofthe present invention connecting a syringe tip to a dental syringe;

FIG. 6 is a cross-sectional view of a sixth embodiment of a fitting ofthe present invention connecting a syringe tip to a dental syringe;

FIG. 7 is a cross-sectional view of a seventh embodiment of a fitting ofthe present invention connecting a syringe tip to a dental syringe;

FIG. 8 is a cross-sectional view of a gripping device of the fitting ofthe present invention, shown in a syringe tip release position;

FIG. 9 is a cross-sectional view showing a portion of a gripping deviceof a seventh embodiment of a fitting of the present invention; and

FIG. 10 is a cross-sectional view showing a portion of the grippingdevice of FIG. 9 in its gripping position.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A fitting for connecting a syringe tip 12 to a medical instrument 14such as an air-water dental syringe is shown in FIG. 1 and generallyindicated at 10. The dental syringe 14 delivers air and water to themouth of a patient and comprises a hand-piece generally indicated at 16.The syringe tip 12 is preferably disposable and is releasably andsealingly engageable with a discharge end 18 of the hand-piece 16. Thefitting 10, or connector assembly, is provided for attachment of thesyringe tip 12 to the dental syringe 14 for conducting fluids to andfrom the syringe and the patient. The fitting 10 is a quick-connectfitting which securely holds the tip 12 in place upon pushing the tipinto the fitting. The fitting 10 includes a gripping mechanism 20 whichprevents removal of the tip 12 from the fitting until a manuallyoperable device 22 is actuated to release the tip from the fitting foreasy replacement of the tip.

The syringe tip 12 (conduit) includes a central passageway 24 extendingalong the length of the tip generally through the center of the tip anda plurality of peripheral passageways 26 surrounding the centralpassageway and extending the length of the tip. The syringe tip 12comprises a generally resilient and pliable elongate inner tube 28extending substantially the entire length of the tip and an outer tube30 which is stiffer than the resilient and pliable material of the innertube. The outer tube 30 concentrically surrounds the inner tube 28 andhas a smooth continuous outer surface. The inner tube 28 may for examplehave a fluted outer surface with elongate flutes spaced about thecircumference of the outer surface. The flutes and the inner surface ofthe outer tube 30 define elongate air passageways 26 (peripheralpassageways) circumferentially disposed about the central fluidpassageway 24 and extending substantially the length of the tube.Preferably, the syringe tip 12 has a generally uniform cross sectionthroughout its entire length. Different tip configurations such as theones shown in U.S. Pat. No. 5,460,619 and U.S. patent application Ser.No. 08/423,994, which are incorporated herein by reference, may also beused with this fitting 10. It is to be understood that the syringe tip12 may have only one fluid passageway or more than two fluid passagewaysand may have configurations other than those described above withoutdeparting from the scope of this invention.

The hand-piece 16 includes a handle portion (not shown) for grasping thehand-piece, a first fluid (water) passage 34 for directing a stream ofwater to the discharge end 18 of the hand-piece 16 and a second fluid(air) passage 36 for directing an air stream to the discharge end of thehand-piece. The hand-piece 16 further includes a threaded socket 38 atits discharge end 18 for threadably receiving the fitting 10 and pushbuttons (not shown) for discharging air, water or a combination of airand water from the hand-piece. The water and air passages 34, 36 extendfrom pressurized sources (not shown) to first and second ports 40, 42 inthe socket.

The fitting 10 comprises an elongate body 44 having a centrallongitudinal axis L_(A) extending between a proximal end 46 and a distalend 48, and a recess 50 extending on the axis from the distal end towardand terminating short of the proximal end thereof. The body 44 isgenerally cylindrical and includes external threads 52 adjacent to theproximal end 46 for threadably engaging internal threads 53 formed onthe socket 38 of the hand-piece 16. The body 44 is formed for attachmentto the dental syringe 14 with the proximal end 46 of the body positionedin the socket 38 of the syringe. A seal 54 is circumferentiallypositioned around the body 44 generally adjacent to the threaded portion52 of the body to prevent leakage of air from between the body and thehand-piece 16.

The proximal end 46 of the body 44 has a bottom 56 having two passages58, 60 formed therein extending from one side of the bottom adjacent tothe hand-piece 16 to the opposite side of the bottom into the recess 50of the body. The first passage 58 extends generally through the centerof the bottom 56 of the body 44 and along the longitudinal axis L_(A) ofthe body. The second passage 60 extends at an angle relative to thefirst passage 58. The distal end 48 of the body 44 is open for receivingthe syringe tip 12. The syringe tip 12 is positioned within the recess50 such that the central passageway 24 in the tip is in communicatingrelation at the end of the tip in the recess in the body 44 with thecentral passage 58 in the bottom 56 of the body and the peripheralpassageways 26 in the tip are in communicating relation at the end ofthe tip in the recess in the body with the second passage 60 in thebottom of the body.

As shown in FIG. 1, the body includes a generally cylindric first bodypart 62 having a threaded proximal end for threaded attachment to thedental syringe 16. The body 44 further includes a collect 66 which isgenerally cup-shaped and has a generally cylindric side wall 68coaxially received inside the proximal end 46 of the first body part 62and an end wall forming the bottom 56 of the body. The body 44 may alsobe formed in more than two pieces or as a one-piece body as shown inFIG. 3 and described further below. The first body part 62 includes ashoulder 70 formed on the inside wall of the body 44 and spacedlongitudinally from the bottom 56 of the body. The shoulder 70 functionsas an internal stop for the proximal end 71 of the syringe tip 12 toprevent the tip from contacting the bottom 56 of the body 44 andpossibly blocking the second passage 60.

The fitting 10 further includes a connector 72 (tubular connector)having a tubular shaped member 74 which extends from the bottom 56 ofthe body 44 into the recess 50 and has a bore 76 therethrough formingthe first passage 58 of the body. The tubular member 74 has a distalpart 78 sized for a sealing fit inside the central passageway 24 of thesyringe tip 12 to provide a fluid-tight sealing connection between thecentral passageway in the tip and the first passage 58 in the bottom 56of the body 44. The distal part 78 of the tubular member is generallynon-tapered and sized for an interference fit inside the centralpassageway 24. The inner tube 28 is sufficiently pliable to expandradially outward when receiving the tubular member 74 as the syringe tip12 is pushed toward its initial position and sufficiently resilient toform the fluid-tight sealing connection continuously around the tubularmember when fluid flows therethrough. The tubular member 74 is axiallyslidable within the inner tube 28 as the syringe tip 12 moves along thelongitudinal axis L_(A) of the body 44. The material of the inner tube28 is sufficiently resilient during the sliding movement to maintain thefluid-tight sealing connection. The tubular member 74 extends from acylindrical base 80 sized for insertion into a recess 81 in thehand-piece 16. The base 80 includes a flange 82 at its upper endadjacent to the bottom 56 of the body 44. The flange 82 and adjacentsurface of the hand-piece 16 form a recess 84 for receiving an O-ring 86for preventing communication of fluid entering the first passage 58 andfluid entering the second passage 60. The tubular connector 72 may haveother configurations including those shown in the alternate embodimentsand further described below.

A quick-connect device 88 is mounted in the recess 50 in the body 44adjacent the distal end 48 of the body for allowing quick connection ofthe syringe tip 12 to the body and quick disconnection of the syringetip from the body. The quick-connect device 88 has an opening 90therethrough generally coaxial with the longitudinal axis L_(A) of thebody 44 for insertion of the tip 12 with the tip extending through thequick-connect device toward the bottom 56 of the body. The quick-connectdevice 88 may be a device such as available from Weatherhead of Toledo,Ohio under model designation number 1161, Norgren of Littleton, Colo.under the model designation 12 008 0200, Legris of Mesa, Ariz. undermodel designation 3175 04 11, LF3000, or Parker of Otsego, Mich. undermodel designation 68PL-5/32-2 or PMCEN-5/32, for example. Quick-connectdevices other than those listed may also be used.

The gripping mechanism 20 is part of the quick-connect device 88 andpermits the proximal end 71 of the syringe tip 12 to be pushed throughthe opening 90 of the quick-connect device 88 to an initial position inthe body recess 50 adjacent the bottom 56 of the body 44. When thesyringe tip 12 is in its initial position, the tubular connector 72provides a fluid-tight sealing connection between the central passageway24 in the syringe tip 12 and the first passage 58 in the bottom 56 ofthe body 44. The syringe tip 12 is mounted within the gripping mechanismfor axial movement in the proximal and distal directions with respect tothe body 44 and permits the syringe tip 12 to move a limited distanceaway from the bottom 56 of the body 44 and its initial position to anoperating position. The gripping mechanism 20 applies a progressivelyincreasing gripping force to the tip 12 as the tip moves away from thebottom 56 until the tip reaches the operating position in which thegripping force prevents substantial further movement of the tip in adistal direction away from the bottom.

The gripping mechanism 20 is responsive to exertion of force on the tip12 tending to move the tip in the direction toward the distal end 48 ofthe body 44 to grip the tip and prevent it from moving out from thecommunicating relationship with the passages 58, 60 in the bottom 56 ofthe body 44. The force may be a manual force applied by a persongrasping the syringe tip 12 and trying to pull it out of the fitting 10or a force exerted on the tip by air or water pressure from thehand-piece 16 tending to push the syringe tip in the distal direction.The syringe tip 12 is rotatable on a longitudinal axis of the tip whilethe syringe tip is in its operating position and while the tip is beinggripped by the gripping mechanism.

When the syringe tip 12 is in its operating position, the proximal end71 of the tip is spaced from the bottom 56 of the body 44 to provide acavity 92 therebetween allowing fluid communication between the secondpassage 60 in the bottom of the body and the peripheral passageways 26in the tip. The tubular connector 72 maintains the fluid-tight sealingconnection between the first passage 58 in the bottom 56 of the body 44and the central passageway 24 in the syringe tip 12.

The gripping mechanism 20 includes the manually operable device 22 formoving the gripping mechanism in a proximal direction relative to thebody 44 to allow the gripping mechanism to move radially outward torelease the syringe tip 12 so that it can be removed from the body andreplaced. The manually operable device 22 comprises a sleeve 94 coaxialwith the longitudinal axis L_(A) of the body 44 and mounted for axialsliding movement relative to the body. The sleeve 94 has a proximal endportion 95 in the recess 50 connected to the gripping mechanism 20 and adistal end portion 97 extending distally beyond the distal end 48 of thebody 44 so that it is accessible to an operator of the instrument to bepushed in a proximal direction to move the gripping mechanism in aproximal direction and radially outward to release the syringe tip 12.

The gripping mechanism 20 further includes a plurality of grippers 96extending from the sleeve 94 toward the bottom 56 of the body 44generally parallel to the longitudinal L_(A) axis of the body. Thegrippers 96 are resiliently biased radially outward as the grippers movein the proximal direction. Movement of the gripping mechanism 20 in theproximal direction allows the grippers to move radially outward relativeto the longitudinal axis L_(A) of the body 44 and movement in the distaldirection causes the grippers to move radially inward toward thelongitudinal axis. It is to be understood that the grippers 96 may beformed as individual fingers, may be integrally formed as a tubularmember or have configurations other than the one shown without departingfrom the scope of this invention.

The quick-connect device 88 includes a tubular insert 98 mounted in therecess 50 surrounding the sleeve 94 and grippers 96. The tubular insert98 has a camming surface 100 engageable by the grippers 96 to move thegrippers radially inward as the grippers move in the distal directionrelative to the body 44 to tightly grip the tip 12 (FIG. 8). The tubularinsert 98 is press fit into the body 44 but it may also be threaded intothe body or held in place by a lock ring or other similar retainingmethods. An O-ring 102 is disposed adjacent one end of the collect 66and a retaining ring 104 holds the O-ring in place. The O-ring preventsleakage of air between the syringe tip 12 and the body 44.

A second embodiment of the fitting of the present invention is shown inFIG. 2 and indicated generally at 110. The fitting 110 is similar to thefitting of the first embodiment but includes a tubular connector 112having a tubular shaped pin 114 for insertion into the syringe tip 12and a flange 116 for positioning the pin adjacent to the bottom 56 ofthe body 44. An O-ring 118 is interposed between the flange 116 and thehand-piece 16. The body includes a recess 117 for receiving the O-ring118 and flange 116. The flange 116 and O-ring 118 are sized so that theO-ring does not block the second passage 60 in the body 44. The flange116 is preferably integrally formed with the pin 114.

FIG. 3 shows a third embodiment of the fitting of the present invention120. The fitting 120 is similar to the fittings 10, 110 shown in FIGS. 1and 2, except for the tubular connector 122. The tubular connector 122includes a base 124, a central member 126, and an elongate member 128extending from one end of the central member. When the base 124 ispositioned between the body 44 and the hand-piece 16, the central member126 extends through the first passage 58 in the body 44 and the elongatemember 12 extends into the central fluid passageway 24 of the syringetip 12. The base 124 has a diameter larger than the first passage in thebody so that the connector is retained in the body when the syringe tipis removed from the body. The tubular connector 122 has an opening 130extending generally along the longitudinal axis L_(A) of the body 44 forproviding fluid communication between the dental syringe 14 and thecentral passageway 24 of the syringe tip 12. The connector 122 isreleasably and removably attached to the body 44 so that the connectormay be easily replaced if the opening gets clogged. For example, thebase 124 of the tubular connector 122 may have a diameter of 0.120 in.,the central member 126 a diameter of 0.069 in. and length of 0.086 in.and the elongate member 128 a diameter of 0.039 in. and a length of0.124 in. A ratio of the diameter of the elongate member 128 to thecentral member 126 of the tubular connector 122 described above is inthe range of 0.48-0.57. The tip of the elongate member may also betapered.

FIG. 4 shows a fourth embodiment of the present invention, generallyindicated at 140. The configuration of the tubular connector 142 issimilar to the tubular connector 122 shown in FIG. 3 except the centralmember 146 and base 144 have a greater thickness and the central member146 extends beyond the bottom 56 of the body 44 and into the recess 50to provide a stop 148 for the syringe tip 12. The body therefore doesnot require a shoulder for positioning the proximal end 71 of thesyringe tip 12.

A fifth embodiment is shown in FIG. 5 and generally indicated at 150.The fitting 150 includes a body 152 having the collect 66 of the firstembodiment integrally formed as one piece with the first body part 62.The body 152 is formed with a shoulder 154 for positioning the tip 12spaced from the bottom 162 of the body 152. A groove 156 is formed inthe body 152 to receive the O-ring 102 for preventing leakage betweenthe tip 12 and the body 152. The opening 168 adjacent the distal end 164of the body 152 is sized for receiving the quick-connect device 88. Theoutside diameter of the proximal end 166 of the body 152 includesthreads 168 for mating with the internal threads 53 formed in the socket38 of the hand-piece 16.

A sixth embodiment of the fitting is shown in FIG. 6 and generallyindicated at 170. The body and tubular connecter are integrally formedas a one-piece body 172. The passages 58, 60 are formed in the proximalend 177 of the body and the tubular connector 179 constitutes the firstpassage. The proximal end 177 of the body 172 includes a projection 174sized for receiving an O-ring 180. The body 172 is formed with ashoulder 182 for positioning the tip 12 spaced from a bottom 184 of thebody. A groove 176 is formed in the body 172 to receive the O-ring 102for preventing leakage between the tip 12 and the body.

A seventh embodiment of the fitting, generally indicated at 190, isshown in FIG. 7. The fitting 190 is configured for receiving a syringetip 192 having an inner tube 194 extending from the proximal end 195 ofthe tube. The inner tube 194 forms a central passageway 193 andconstitutes the tubular connector. The collect 66 includes a groove 191for receiving an O-ring 197.

FIGS. 9 and 10 show a portion of a quick-connect device, generallyindicated at 200, of an eighth embodiment of the fitting. The cammingsurface 202 of the tubular insert 204 comprises a distal portion 206having a frictionalized surface 208 to prevent rotation of the gripper210 and syringe tip 12 on a longitudinal axis of the tip when thegripper is engaged with the distal portion of the camming surface whenthe tip is in its operating position. The grippers 210 also have africtionalized surface 211 for engagement with the camming surface 202of the tubular insert 204. It is to be understood that only one of thegrippers 210 or distal portion 206 of the camming surface 202 may have africtionalized surface or the grippers and distal portion of the cammingsurface may have interlocking surfaces such as splines to preventrotation of the syringe tip by preventing rotation of the sleeve withinthe tubular insert when the syringe tip is in its operating position.

In operation, the fitting 10 is threaded into the socket 38 of thehand-piece 16 and the syringe tip 12 is pushed through the opening 90 inthe quick-connect device 88 to the initial position in which theproximal end 71 of the syringe tip is adjacent the bottom 56 of the body44 and the central passageway 24 of the syringe tip has a fluid-tightconnection to the first passage 58 in the bottom of the body. Thesyringe tip 12 is then moved in a direction away from the bottom 56 ofthe body 44 while maintaining the fluid-tight sealing connection,thereby causing the gripping mechanism 20 to apply a progressivelyincreasing gripping force to the syringe tip until the syringe tipreaches the operating position in which the gripping force preventssubstantial further movement of the syringe tip in a distal directionaway from the bottom. Any force exerted on the tip 12 to move the tip inthe direction toward the distal end 48 of the body 44 will cause thegripping device 20 to tighten the grip of the grippers 96 on the syringetip. The syringe tip 12 is preferably pulled in the direction toward thedistal end 48 of the body 44 to ensure that the tip is securely held inplace. The water or air button is then depressed to force air or waterfrom its respective ports 40, 42 in the hand-piece 16 and through thefluid passageways 26, 26 of the syringe tip 12. When the dentalprocedure has been completed, the syringe tip 12 is removed from thefitting 10 and discarded. In order to remove the tip 12, the manuallyoperable device 22 is pushed in a proximal direction to cause thegrippers 96 of the gripping mechanism 20 to move radially outward torelease the syringe tip while the tip is pulled out from the body 44.

Although the fitting 10 is described herein as being used for connectingsyringe tips 12 to dental syringes 14, it is to be understood that thefitting may be used with other types of dental instruments or variousother instruments used in the medical field. For example, the fitting 10may be used in other dental applications such as for air-abrasiveprophylaxis (air polishers), endodontic (root canal)irrigator-aspirators or oral hygiene apparatus. Medical applications forthe fitting include ophthalmic surgery irrigator-aspirators, generalsurgery irrigator-aspirators (lavage), dual lumen catheters andatomizers.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above constructions and methodswithout departing from the scope of the invention, it is intended thatall matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

What is claimed is:
 1. A fitting for releasably and sealingly connectinga conduit to a medical instrument, the instrument having a socket forreceiving the fitting and first and second ports for transfer of firstand second fluids to and from the socket, and said conduit having acentral passageway therethrough for conducting said first fluid and oneor more peripheral passageways therethrough for conducting said secondfluid, said fitting comprising;a body having a proximal end, a distalend and a longitudinal axis extending between said ends; said bodyhaving a recess extending on said axis from said distal end toward andterminating short of said proximal end thereof, said body having abottom adjacent its proximal end and being open at its distal end; saidbody being formed for attachment to said medical instrument with theproximal end of the body positioned in the socket of the instrument; atubular connector extending from the bottom of the body into the recesshaving a bore forming a first passage for delivering said first fluid tothe central passageway of the conduit, the connector including a tubularmember having a distal part sized for connection to the centralpassageway of the conduit to provide a fluid-tight sealing connectionbetween the first passage and the central passageway in the conduit; asecond passage extending through the body for delivering said secondfluid to the conduit; a quick-connect device mounted in the recess inthe body adjacent the distal end of the body for allowing quickconnection of the conduit to the body and quick disconnection of theconduit from the body, said quick-connect device having an openingtherethrough generally coaxial with said longitudinal axis of the body;said quick-connect device comprising a gripping mechanism adjacent saidopening, the conduit being receivable in the gripping mechanism foraxial movement in proximal and distal directions with respect to saidbody, movement of the conduit in the proximal direction allowing thegripping mechanism to move radially outward relative to the longitudinalaxis of the body and movement in the distal direction causing thegripping mechanism to move radially inward toward said longitudinalaxis, said gripping mechanism permitting one end of the conduit,constituting its proximal end, to be pushed through the opening of thequick-connect device to an initial position in said body recess adjacentthe bottom of the body, said initial position being one in which thetubular connector is adapted to provide the fluid-tight sealingconnection between the central passageway in the conduit and the firstpassage in the connector; said gripping mechanism being responsive to aforce on the conduit in a distal direction to permit the conduit to movea limited distance away from the bottom of the body, said grippingmechanism further being operable to apply a progressively increasinggripping force to the conduit as the conduit moves away from said bottomuntil the conduit reaches an operating position in which said grippingforce prevents substantial further movement of the conduit in a distaldirection away from said bottom, said operating position being one inwhich the proximal end of the conduit is spaced from the bottom of thebody to provide a cavity therebetween allowing fluid communicationbetween said second passage in the bottom of the body and said one ormore peripheral passageways in the conduit, and in which said tubularconnector is adapted to maintain said fluid-tight sealing connectionbetween said first passage in the bottom of the body and said centralpassageway in the conduit; and manually operable means for moving saidgripping mechanism in a proximal direction relative to the body to allowthe gripping mechanism to move radially outward to release the conduitso it can be removed from the body.
 2. A fitting as set forth in claim 1wherein said conduit is rotatable on a longitudinal axis of the conduitwhile the conduit is gripped by the gripping mechanism.
 3. A fitting asset forth in claim 1 wherein said body has an internal stop spacedlongitudinally from the bottom of the body, said stop being engageableby the proximal end of the conduit when it is inserted into the recessof the body to prevent the conduit from contacting the bottom of thebody.
 4. A fitting as set forth in claim 1 in combination with saidconduit, said conduit having an inner tube of resilient and pliablematerial defining said central passageway, and an outer tube of amaterial which is stiffer than said resilient and pliable material andwhich concentrically surrounds the inner tube, and wherein the distalend part of the tubular member is generally non-tapered and sized for aninterference fit inside said central passageway, the inner tube beingsufficiently pliable to expand radially outward when receiving thetubular member as the conduit is pushed toward its said initialposition, and sufficiently resilient to form said fluid-tight sealingconnection continuously around the tubular member when fluid flowstherethrough, said tubular member being axially slidable within saidinner tube as the conduit moves from its initial position toward itssaid operating position, said inner tube material being sufficientlyresilient during such sliding movement to maintain said fluid-tightsealing connection.
 5. A fitting as set forth in claim 4 wherein saidtubular member is formed as an integral part of the body.
 6. A fittingas set forth in claim 4 wherein said tubular member is separate from thebody.
 7. A fitting as set forth in claim 1 wherein said manuallyoperable means comprises a sleeve coaxial with said longitudinal axis ofthe body mounted for axial sliding movement relative to the body, saidsleeve having a proximal end portion in the recess connected to thegripping mechanism, and a distal end portion extending distally beyondthe distal end of the body so that it is accessible to an operator ofthe instrument to be pushed in a proximal direction to move saidgripping mechanism in a proximal direction and radially outward torelease said conduit.
 8. A fitting as set forth in claim 7 wherein saidgripping mechanism comprises a plurality of grippers extending from saidsleeve toward the bottom of the body generally parallel to thelongitudinal axis of the body, said quick-connect device furthercomprising a tubular insert mounted in the recess surrounding the sleeveand grippers, said tubular insert having a camming surface engageable bythe grippers to move the grippers radially inward as the grippers movein a distal direction relative to the body, said grippers beingresiliently biased radially outward as the grippers move in a proximaldirection.
 9. A fitting as set forth in claim 8 wherein said cammingsurface comprises a distal portion having a frictionalized surface toprevent rotation of the gripper and conduit on a longitudinal axis ofthe conduit when the gripper is engaged with the distal portion of thecamming surface.
 10. A fitting as set forth in claim 1 wherein said bodycomprises a generally cylindric first body part having a threadedproximal end for threaded attachment to the medical instrument, and asecond generally cup-shaped collet having a generally cylindric sidewall coaxially received inside the proximal end of said first body part,and an end wall forming the bottom of the body, said gripping mechanismbeing disposed inside the first body part distally of the collet.
 11. Afitting as set forth in claim 10 further comprising sealing means insidethe first body part between the collet and said gripping mechanism forsealing against the passage of fluid from said cavity.
 12. A medicalsyringe comprising hand-piece for transporting first and second fluidsbetween a patient and the syringe, a socket in the hand-piece, a syringetip having a central passageway therethrough for conducting said firstfluid and one or more peripheral passageways therethrough for conductingsaid second fluid, wherein the improvement comprises a tip connectorassembly for releasably and sealingly connecting the syringe tip to thehand-piece, said tip connector assembly comprising;a body having aproximal end, a distal end and a longitudinal axis extending betweensaid ends, said body having a recess extending on said axis from saiddistal end toward and terminating short of said proximal end thereof,said body having a bottom adjacent its proximal end and being open atits distal end; said body being formed for attachment to said hand-piecewith the proximal end of the body positioned in the socket of thehand-piece; first and second passages through the bottom of the body forflow of said first and second fluids, respectively; a quick-connectdevice mounted in the recess in the body adjacent the distal end of thebody for allowing quick connection of the syringe tip to the body andquick disconnection of the syringe tip from the body, said quick-connectdevice having all opening therethrough generally coaxial with saidlongitudinal axis of the body; said quick-connect device comprising agripping mechanism adjacent said opening, said syringe tip beingreceivable in the gripping mechanism for axial movement in proximal anddistal directions with respect to said body, movement of the syringe tipin the proximal direction allowing the gripping mechanism to moveradially outward relative to the longitudinal axis of the body andmovement in the distal direction allowing the gripping mechanism to moveradially inward toward said longitudinal axis, said gripping mechanismpermitting one end of the syringe tip, constituting its proximal end, tobe pushed through the opening of the quick-connect device to an initialposition in said body recess adjacent the bottom of the body; a tubularconnector extending from the bottom of the body having a distal partsized and shaped for connection to the central passageway of the syringetip for maintaining a fluid-tight sealing connection between the centralpassageway in the syringe tip and the first passage in the bottom of thebody when the proximal end of syringe tip is in said initial positionadjacent the bottom of the body; said gripping mechanism beingresponsive to a force on the syringe tip in a distal direction to permitthe syringe tip to move a limited distance away from the bottom of thebody, said gripping mechanism further being operable to apply aprogressively increasing gripping force to the syringe tip as thesyringe tip moves away from said bottom until the syringe tip reaches anoperating position in which said gripping force prevents substantialfurther movement of the syringe tip in a distal direction away from saidbottom, said operating position being one in which the proximal end ofthe syringe tip is spaced from the bottom of the body to provide acavity therebetween allowing fluid communication between said secondpassage in the bottom of the body and said one or more peripheralpassageways in the syringe tip, and in which said tubular connectormaintains said fluid-tight sealing connection between said first passagein the bottom of the body and said central passageway in the syringetip; and manually operable means for moving said gripping mechanism in aproximal direction relative to the body to allow the gripping mechanismto move radially outward to release the syringe tip so it can be removedfrom the body.
 13. A medical syringe as set forth in claim 12 whereinsaid syringe tip is rotatable on a longitudinal axis of the syringe tipwhile the syringe tip is gripped by the gripping mechanism.
 14. Amedical syringe as set forth in claim 12 wherein said body has aninternal stop spaced longitudinally from the bottom of the body, saidstop being engageable by the proximal end of the syringe tip when it isinserted into the recess of the body to prevent the syringe tip fromcontacting the bottom of the body.
 15. A medical syringe as set forth inclaim 12 wherein said tubular connector comprises a tubular memberextending from the bottom of the body into the recess and having a boretherethrough forming said first passage, said tubular member having adistal part sized for a sealing fit inside the central passageway of thesyringe tip to provide said fluid-tight sealing connection between thecentral passageway in the syringe tip and the first passage in thebottom of the body.
 16. A medical syringe as set forth in claim 15wherein said syringe tip comprises an inner tube of resilient andpliable material defining said central passageway, and an outer tube ofa material which is stiffer than said resilient and pliable material andwhich concentrically surrounds the inner tube, and wherein the distalend part of the tubular member is generally non-tapered and sized for aninterference fit inside said central passageway, the inner tube beingsufficiently pliable to expand radially outward when receiving thetubular member as the syringe tip is pushed toward its said initialposition, and sufficiently resilient to form said fluid-tight sealingconnection continuously around the tubular member when fluid flowstherethrough, said tubular member being axially slidable within saidinner tube as the syringe tip moves from its initial position toward itssaid operating position, said inner tube material being sufficientlyresilient during such sliding movement to maintain said fluid-tightsealing connection.
 17. A medical syringe as set forth in claim 16wherein said tubular member is formed as an integral part of the body.18. A medical syringe as set forth in claim 16 wherein said tubularmember is separate from the body.
 19. A medical syringe as set forth inclaim 12 wherein said manually operable means comprises a sleeve coaxialwith said longitudinal axis of the body mounted for axial slidingmovement relative to the body, said sleeve having a proximal end portionin the recess connected to the gripping mechanism, and a distal endportion extending distally beyond the distal end of the body so that itis accessible to an operator of the instrument to be pushed in aproximal direction to move said gripping mechanism in a proximaldirection and radially outward to release said syringe tip.
 20. Amedical syringe as set forth in claim 19 wherein said gripping mechanismcomprises a plurality of grippers extending from said sleeve toward thebottom of the body generally parallel to the longitudinal axis of thebody, said quick-connect device further comprising a tubular insertmounted in the recess surrounding the sleeve and grippers, said tubularinsert having a camming surface engageable by the grippers to move thegrippers radially inwardly as the grippers move in a distal directionrelative to the body, said grippers being resiliently biased radiallyoutward as the grippers move in a proximal direction.
 21. A medicalsyringe as set forth in claim 12 wherein said body comprises a generallycylindric first body part having a threaded proximal end for threadedattachment to the medical instrument, and a second generally cup-shapedbody part having a generally cylindric side wall coaxially receivedinside the proximal end of said first body part, and an end wall at adistal end of the collect forming the bottom of the body, said grippingmechanism being disposed inside the first body part distally of thecollet.
 22. A fitting as set forth in claim 21 further comprisingsealing means inside the first body part between the collet and saidgripping mechanism for sealing against the passage of fluid from saidcavity.
 23. A method of connecting a syringe tip to a hand-piece used totransport first and second fluids between a patient and the hand-piece,said syringe tip being of the type having a central passagewaytherethrough for conducting said first fluid and one or more peripheralpassageways therethrough for conducting said second fluid, and saidhand-piece being of the type having a fitting comprising an elongatebody having a distal end, a proximal end, a longitudinal axis extendingbetween said ends, and a recess extending from the distal end toward andterminating short of the proximal end of the body, the body having abottom at its proximal end, a first passage for flow of said first fluidthrough the bottom of the body, a second passage for flow of said secondfluid through the bottom of the body, a tubular connector extending fromthe bottom of said recess and being in fluid communication with saidfirst passage, and a quick-connect device mounted in the recess in thebody having an opening therethrough, said quick-connect devicecomprising a gripping mechanism adjacent said opening, said syringe tipbeing receivable in the gripping mechanism for axial movement inproximal and distal directions with respect to said body, movement ofthe syringe tip in the proximal direction causing the gripping mechanismto move radially outwardly relative to the longitudinal axis of the bodyand movement in the distal direction causing the gripping mechanism tomove radially inwardly toward said longitudinal axis, said grippingmechanism permitting a proximal end of said syringe tip to be pushedthrough the opening of the quick-connect device and being responsive toa force on the syringe tip in a distal direction to permit the syringetip to move a limited distance in the distal direction, said grippingmechanism further being operable to apply a progressively increasinggripping force to the syringe tip as the syringe tip moves in saiddistal direction until the syringe tip moves said limited distancewhereupon the syringe tip direction, said method comprising:pushing thesyringe tip through the opening in the gripping device to an initialposition in which the proximal end of the syringe tip is adjacent thebottom of the body and the central passageway in the syringe tip has afluid-tight sealingly connection to the tubular connector in the bottomof the body; and while maintaining said fluid-tight sealing connection,moving the syringe tip in a direction away from the bottom of the bodythereby causing said gripping mechanism to apply a progressivelyincreasing gripping force to the syringe tip until the syringe tipreaches an operating position in which the gripping force preventssubstantial further movement of the syringe tip in a distal directionaway from said bottom, said operating position being one in which theproximal end of the syringe tip is spaced from the bottom of the body toprovide a cavity therebetween allowing fluid communication between saidsecond passage in the bottom of the body and said one or more peripheralpassageways in the syringe tip, and in which said fluid-tight sealingconnection between said tubular connector in the bottom of the body andsaid central passageway in the syringe tip is maintained.
 24. A methodas set forth in claim 23 wherein said fitting has manually operablemeans mounted on the body for axial movement relative to the body forreleasing said gripping mechanism, said method further comprisingpushing said manually operable means in a proximal direction to causethe gripping mechanism to move radially outward to release the syringetip, and then pulling the syringe tip out of the body.